Helix former



April 8, 1952 H. l.. KlTsELMAN 2,591,943

HELIX FORMER Filed Sept. 21, 1948 2 SHEETS-SHEET 1 f \.1 \1 A x 1 E J* A)HUI III l I WI lfm H [Il HIIII H. L. KITSELMAN April s, 1952 HELIXFORMER Y 2 SHEETS-SHEET 2 Filed Sept. 21, 1948 Patented Apr. 8, `1952stares PATENT Harry L. Kitselman, Muncie, Ind., assigner to KitselmanBrothers, Muncie, Indi, a. corporatien offndiana Application September21, 1948. ScrialrNu. 50,2794l e' claims. (C1. 15a-64)- Usually, thedeiiection of the wire is effected by two series of teeth which arebrought into meshing engagement with' the wire between them, thewire-engaging surfaces of the teeth being formed to deiiectA the wireinto the desired helical form. So far as I am aware, the teeth of priorhelixforming machines have been provided with Wirereceiving grooves thebottoms of which conform to the inner surface of the desired` helix forapproximately one-half a helix-turn and theV sides of which areoutwardly to receive the wire and guide it into the groove-bottoms asthe teeth move into full meshingk engagement. Considerable difficultyhas been experienced in producing such teeth with properly shapedgrooves. Because of the complicated shape of each toothgroove itispractically impossible to finish it by machining.; and as a result, thegroove-surfaces must either be finished by hand or the tooth must beformed as a casting. Because of the difficulty in estimating the degreeof over-bending which must be imparted to the wire in order that thehelix Will have the proper dimensions when released from the formingteeth, it is exceedingly diiicult to form by casting teeth which willpossess the necessary groove-shape.

It is the object of my invention to provide a helix-forming machine ofthe type indicated with teeth having wire-deflecting surfaces which canbe shaped by simple machining operations. Another object of my inventionis to simplify and lessen the cost of machines which form helixes bylateral deection of a wire. Still another object of my invention is toproduce a machine in which it is possible to correct or compensate forinaccuracies in tooth formation and, within limits, to Vary the shape ofthe helix produced without changing the form of the teeth.

In carrying out my invention, I employtwo series of meshing teeth,desirably mounted on theperipheries of two co-planar disks. Each of suchteeth is formed with a pair of convexwiredeecting surfaces cylindricalin the sense that each. can be regarded as traced by a straight line,called generatrix or element, moving always parallel to a fixed straightline. The rectilinear elementsA of each wire-deflecting surface aregenerally parallel to the common plane of the axes of the two disks,andl the elements of adjacent wire-deflecting surfaces make equal andopposite angles'with the plane in which the two disks rotate. Desirably,each tooth is mounted in its associated disk for rotative adjustmentabout an axis radial of such disk and alsol for rectilinear adjustmentalong a disk-radius. Means are providedv for guiding wire intoassociation with the meshing teeth; and as the disks are rotated, theoppositely disposed wire-deecting surfaces on the meshing teeth deflectthe wire into the form of a helix.

The accompanying drawings illustrate my invention: f

Fig. 1 is a side elevation of a helix-forming machine; Fig. 2 is avertical section on the line 22 of Fig. l; Fig. 3 is a fragmentalelevation similar to-Fig. 1 but on an enlarged scale, showing a portionof one of the disks broken away to illustrate the tooth-mounting; Fig. 4is a fragmental section on the line 4 4', of Fig. 3; Fig. 5 is anVisometric view illustrating a pair of meshing, helix-forming teeth;Figs. 6 and 7 are side and end elevations respectively of a tooth ofmodified construction; and Fig. 8 is an end elevation ofa tooth ofmodified shape.

The machine shown in the drawings comprises a frame I0 rotatablysupporting two vertically spaced horizontal shafts I I and I2. One ofthe shafts, shown as the shaft II, is adapted for connection to adriving means, as by mounting rigid with it a drive sprocket i3; and thetwo shafts are operatively interconnected to rotate at equal speeds bygears I 4 and I 5.

Each' of the shafts II and I2 carries a disk or wheel I6 provided with acircumferentially extending series of wire-defiecting teeth Il. Thewheels I6 are shown as of the same diameter and the shafts II and I2 asso spaced that the teeth I1 on one wheel mesh with the teeth I1 of theother wheel as the wheels rotate. Each of the teethV I1 (see Fig. 3)embodies a head 20 and a cylindrical shank 2|, and the wheels I6 areprovided in their outer faces with annular series of cylindricalrecesses 22 adapted to receive the Shanks 2| of the respective teeth.Desirably, the shanksZI' and the recesses 22 are circular incross-section, so that each tooth can be rotated about its ovv-n axis.If such a construction is employed", means are provided for clampingeachJ tooth in fixed position about its axis of mounting in theassociated wheel IE. One form of suitable clamping mechanism isillustrated in Fig. 4 and embodies a clamp member 23 slidably mounted ina hole 2d extending through the Wheel I6 at one side of the recess 22.The clamp 23 is provided with an axial, screw-threaded hole forv thereception of a clamp-screw 25 which extends through a washer 26 into thehole 24. One side of the clamp member 23 is beveled, as indicated at 2lto engage the side of the associated tooth-shank 2| and clamp such shankin xed position when the clamp screw 25 is tightened.

In addition to being adjustable about its own axis, each of the teeth isdesirably adjustable radially of its associated wheel IB'. To this end,a screw-threaded hole SG extends inwardly of the wheel I6 from thebottom of veach .recess 22, such hole receiving an adjusting screw 3iupon the outer end of which the shank 2l of the associated teeth isseated. To adjust any tooth in its associated wheel, the clamp screw 25adjacent such tooth is loosened, and the tooth is removed from therecess 22. The screw 2l is then adjusted inwardly or outwardly to thedesired extent and the tooth is replaced in the recess 22. With theinner end of the tooth-shank seated on the screw Si, the tooth isadjusted about its own axis to the desired angular position, and theclamp-screw 25 is retightened.

The head 2S of each tooth is shaped to provide two wire-deflectingsurfaces each of which is convex and cylindrical in the sense that itmay be regarded as generated by a straight line moving always parallelwith itself. The surfaces 35 9..

may be provided on the tooth-body itself, as in the teeth shown in Figs.3, 4, and 5, or they may be provided on inserts 35 of wear-resistantmetal secured to the tooth-body as by soldering or brazing, as shown inFigs. 6 and 7. The two wire-engaging surfaces 35 of each tooth lie onopposite sides of the medium plane of the tooth with thesurface-elements parallel thereto, and the rectilinear elements of eachsurface make equal and opposite angles with a second plane whichcontains the tooth-axis and is perpendicular to the median plane.Preferably, such angles are approximately so that in one elevation (seeFig. '7) the two surfaces 35 appear to define a groove having sidesdisposed at approximately 90 to i each other. Each siu'face, however,continues inwardly of the tooth well beyond the bottom of such groove.

The teeth are set in the disks l5, as indicated in Fig. 3, so that asthe disks rotate a wire 4S i fed between them from a guide 4l will bereceived in the grooves formed lby the oppositely sloping surfaces ofthe successive teeth. The teeth mesh to a depth sufficient to cause thewire to be deected alternately in opposite directions in the commonplane of the disks I6; and as such deformation of the wire is effectedby surfaces which are inclined to such plane, the wire is also deflectedalternately in opposite directions away from that plane. The thicknessof each tooth at the pitch line is approximately equal to onehalf of thepitch of the helix to be formed, and each individual surface 35 formsone-fourth of a helix turn. To prevent interference between the teeth asthey revolve with the disks, the flanks of the teeth are relieved, asindicated at 31.

The precise shape, in end elevation, of a helix produced by my machinewill depend principally on the cross-sectional shape of the surfaces 35.

The depth to which the teeth mesh affects the diameter of the helixproduced and can be varied considerably without materially altering thecross-sectional shape of the helix. In general, to produce a helix ofapproximately circular cross-section the crown or camber of each surface35 should be appreciably greater than that of a similarly disposedsur-face which would t against the inner surface of the helix-wire. Insome cases the cross-sectional shape of the helix can be made morenearly circular by rotating the teeth slightly about their respectiveaxes in the disks I1 so that the median plane of each tooth will be at aslight angle to the disk-axis. To provide for such tooth-adjustment, theheads of the teeth may be of circular cross-section, as shown in Fig. 8.I

As the wire-deflecting surfaces of my improved teeth lare cylindrical,they can be produced by forming cutters or tools or by properly shapedgrinding wheels. Where the inserts 35' of Figs. 6 and 'i are used, thoseinserts may be lengths of strip stock of proper cross-section.

In the machine shown in the drawing, the wire-forming teeth constitute acontinuous series extending for the entire periphery of each disk i'Band are therefore adapted to form a continuous helix of any desiredlength. It will be appreciated, however, that by the omission of alimited number of successive teeth, the machine can be adapted to form awire to provide spaced helical portions. Further, by providing betweensuccessive groups of helix-forming teeth other types of wire-bendingelements, a stretch of wire between two helically formed portions can bebent into any of a wide variety of forms.

These and other possible modifications of the machine illustrated formno part of my present invention, which is directed to a type ofhelixforming tooth and to a machine employing two series of such teethto deform a wire progressively into a helical shape.

I claim as my invention:

1. In a machine for forming a wire into a helix by lateral deflection,two series of spaced teeth movable successively into meshing engagementfrom opposite sides of the wire to be deflected, each of said teethhaving a pair of oppositely inclined, convex cylindrical,wire-deflecting surfaces which lie on opposite sides of a medial planegenerally normal to the wire being formed and which are adapted to formcontiguous fourths of a helix-turn. 2. The invention set forth in claim1 with the addition that said machine embodies two coplanar, rotatabledisks and means for rotating such disks in opposite directions, said twoseries of teeth being mounted respectively on said disks incircumferentially extending arrangement.

3. The invention set forth in claim 1 with the addition that saidmachine includes a movable supporting means for each series of teeth,said supporting means having for each tooth a mounting in which thetooth is rotatably adjustable to vary the angular relationship betweenits median plane and its path of movement.

4. The invention set forth in claim 1 with the addition that saidmachine includes a movable supporting means for each series of teeth,said supporting means including for each tooth a mounting in which thetooth is adjustable toward and away from the axis of the helix beingformed whereby to vary the depth to which it meshes with the teeth ofthe other series.

5. The invention set forth in claim 1 with the addition that saidmachine includes a movable supporting means for each series of teeth,each the teeth being provided with cylindrical Shanks rotatablyreceivable in said recesses, adjustable means for locating eachtooth-shank axially of its associated recess, and releasable means forclamping each tooth-shank in fixed position.

6. The invention set forth in claim 1 with the f addition that thewire-deflecting surfaces of each tooth are provided respectively oninserts secured to the tooth.

HARRY L. KITSELMAN.

REFERENCES CITED The following references are of record in the le ofthis patent:

5 UNITED STATES PATENTS Number Name Date 1,589,798 Ewers June 22, 1926'1,657,695 Richardson Jan.` 31, 1928 -2,148,914 Terhaar Feb. 28, 1939 102,317,530 Holmes et al. Apr. 27, 1943 l2,435,414 Sziklai et al Feb. 3,1948 FOREIGN PATENTS Number Country Date Great Britain of 1885

